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Molalla Pioneer: Threatened Minnow Found In Molalla River Basin

An ODFW Native Fish Investigation team has found the first Oregon chub in the Molalla River since Eisenhower was president.

ODFW’s Native Fish Investigations Program recently teamed up with the Molalla River Watch. The result – the first sighting of Oregon chub in the lower Willamette basin in 60 years.

In more good news for followers of this threatened native minnow, NFI staff recently discovered two populations of Oregon chub in the Molalla River Basin.

Historically, Oregon chub occupied the Willamette River from the mouth of the Clackamas to the Coast Fork and Middle Fork of the Willamette River. However, the last observation of Oregon chub in the lower Willamette was at Oregon City in 1953. Since 1991, ODFW’s Native Fish Investigations Program has conducted surveys at over 50 locations in the lower Willamette in an attempt to locate this species, without success.

In 2013, NFI partnered with the Molalla River Watch to identify and survey additional locations in the Molalla River basin. Oregon chub were found at two sites, one on Milk Creek near the town of Canby, the other near the town of Molalla. Oregon chub had not been documented in the Molalla basin previously. This finding extends the range of Oregon chub 70 river miles north.

Although }populations were historically documented below Willamette falls, the current known distribution is close to the historical distribution of Oregon chub.

Nonnative fish species, such as largemouth bass and bluegill, predate upon and compete with Oregon chub, and are common in the off-channel and slow flowing habitats preferred by chub. The impact of nonnative fish, combined with the alteration or loss of many off-channel habitats and changes in river flow due to the construction of the Willamette dams, led ODFW to believe that Oregon chub were likely extirpated from the lower Willamette.

NFI staff are planning to seek out and collaborate with partners in the Molalla basin in 2014 and beyond to sample additional areas. In addition, NFI will seek out public and private landowners that are willing to allow introductions of Oregon chub into suitable habitat, to increase the number of populations and add resiliency for the species.